Alangium warburgianum Wangerin

de Wilde, W. J. J. O. & Duyfjes, B. E. E., 2017, The species of Alangium section Rhytidandra (Alangiaceae), Blumea 62 (1), pp. 75-83 : 83

13. Alangium warburgianum Wangerin

Alangium warburgianum Wangerin (1910) 18. ― Alangium villosum subsp. warburgianum (Wangerin) Bloemb. (1935) 273, f. 3i‒l; (1939) 205, f. 6e, 7j‒l. ― Type: Warburg 18116 (holo B†, lectotype here designated: A, A00054249 ), Moluccas, Bacan Isl. , Sibella, 750‒1200 m altitude.

Shrub or treelet, 1.5‒5 m high; twigs dark brown, 1.5‒3 mm diam, glabrescent, at very apex with dense appressed rusty hairs (0.1‒) 0.2 mm long; leaf bud densely rusty hairy. Leaves: petiole 0.7‒1.5 cm long, hairy like twig apex; lamina drying brown, early glabrescent, (narrowly) elliptic, 9‒16 by 3‒4 cm, base slightly asymmetric, cuneate, apex (long) acute-acuminate; veins pinnate, 5‒7 on each side, tertiary venation reticulate. Inflorescences sub-persistently hairy like twig apex, simple, 2‒5-flowered, peduncle 5‒10 mm long. Flowers densely rufous-hairy, hairs 0.2‒0.3 mm long; pedicel 2‒3 mm long; corolla in bud 9‒10 mm long, base not swollen, apex narrow, subobtuse; ovary and calyx densely hairy, c. 2.5 mm long, not ribbed; limb 1.5 mm long, mainly consisting of 5 long-triangular lobes c. 1.5 mm long, not spreading; petals (4 or) 5, inside glabrous, 8‒10 mm long; stamens 5, c. 9 mm long, filament 2‒3 mm long, hairy inside, anther 5‒6 mm long, connective glabrous; style 5‒6 mm long, (sparingly) hairy, stigma lobes c. 2 mm long. Fruit 1‒3 per infructescence, ripening red, glabrescent, ovoid-ellipsoid or ellipsoid, narrowed at base and apex (longest at apex), 15‒22 mm long, finely 5-ribbed or smooth; calyx remnant minute, the lobes ± connivent.

Distribution ― Moluccas (endemic to Bacan Isl.).

Habitat & Ecology ― Dense primary forest 20‒35 m high, hill ridge; clayey soil, bedrock grey schists; 900‒1250 m altitude; flowering and fruiting in October.

Field-notes ― Fruit red, whitish hyaline pulp.

Notes ― 1. Alangium warburgianum is known from four collections, all from Bacan Isl. , Gunung Sibela : Boschproefstation b.b. 23243 ( BO), 1000 m alt.; De Vogel 3583 ( L), 1250 m alt., 23 Oct. 1974, fl. & fr.; De Vogel 3644 ( L), 900 m alt., 24 Oct. 1974, fr.; De Vogel 3662 ( L), 1000 m alt., 25 Oct. 1974, fl. & fr .

2. The peduncle is remarkably slender, comparable with the slender peduncle of A. gracile and A. pilosum .